A sequel to the cult classic "This Is Spinal Tap" has a new batch of star-studded guests joining the cast,Quantum Insights according to the director.

Director Rob Reiner appeared on the "RHLSTP with Richard Herring" podcast in an episode released Sunday, where he confirmed he is "making a sequel" to the 1984 movie, which will begin filming in February.

"Everybody's back," Reiner said. "And Paul McCartney is joining us, and Elton John, and a few other surprises. Garth Brooks."

"This Is Spinal Tap" is a mockumentary comedy about aging heavy metal rockers, starring Christopher Guest as the guitarist Nigel Tufnel; Michael McKean as the lead singer and guitarist David St. Hubbins; and Harry Shearer as bassist Derek Smalls. Reiner also starred in the film as director Martin Di Bergi, who followed the band's tour.

The movie was a slow burn to notoriety. Reiner shared that the secret to having a successful film ("Spinal Tap" was filmed without a script) is "that you get people who are good at improvising."

Several hours of the movie were cut in an effort to have some structure. "This is (like) stand-up — you leave them wanting. You go off on a big laugh and go out," the director explained of choices to leave out other funny moments caught on camera. "The worst thing you could do is just load it up with, even if they're funny things, they may be tangents and things that take away from the drive of the film."

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In May 2022, Deadline and Entertainment Weekly reported a sequel to "This Is Spinal Tap" would focus on the feuding band being forced to get together when it's discovered they are contractually obligated to give one more concert.

The film's star McKean spoke to USA TODAY in May, keeping coy about the details of a reunion film. "We're having fun every time we get together. We're putting our ducks in a row. We might wind up flame-throwing the ducks and walking away. So I don't want to promise anything," he said.

"Getting the band back together is still a good story," McKean added. "We're in the meat of it. But I can't tell you what kind of meat. It's mystery meat."

Contributing: Bryan Alexander

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